LncRNA DICER1-AS1 promotes the proliferation, invasion and autophagy of osteosarcoma cells via miR-30b/ATG5

LncRNA B4GALT1-AS1 recruits HuR to promote osteosarcoma cells stemness and migration via enhancing YAP transcriptional activity

OBJECTIVES

This study aims to reveal the roles and related mechanisms of LncRNA B4GALT1-AS1 in osteosarcoma (OS) cells stemness and migration.

MATERIALS AND METHODS

Real-time quantitative PCR (RT-qPCR) was used to detect the expression of several LncRNAs in OS tissues and normal adjacent tissues and in OS mammospheres and cells. Cell viability, transwell migration, tumour spheres formation and in vivo tumour formation assays were used to examine the effects of LncRNA B4GALT1-AS1 on OS progression. In addition, RNA immunoprecipitation (RIP) and Luciferase reporter assays were performed to determine the binding site of RNA-binding protein HuR on B4GALT1-AS1 and transcriptional factor YAP. Immunofluorescence analysis was used to examine YAP nuclear-cytoplasm translocation.

RESULTS

LncRNA B4GALT1-AS1 expression was significantly increased in OS tissues and cells spheres. Knockdown of B4GALT1-AS1 inhibited OS cells proliferation, migration, stemness and chemotherapeutic sensitivity. Mechanistically, B4GALT1-AS1 recruited HuR to enhance YAP mRNA stability and thus its transcriptional activity.

CONCLUSIONS

We indicate that lncRNA B4GALT1-AS1 promotes OS cells stemness and migration via recruiting HuR to enhance YAP activity.

Emerging roles of long non-coding RNAs in tumor metabolism

Compared with normal cells, tumor cells display distinct metabolic characteristics. Long non-coding RNAs (lncRNAs), a large class of regulatory RNA molecules with limited or no protein-coding capacity, play key roles in tumorigenesis and progression. Recent advances have revealed that lncRNAs play a vital role in cell metabolism by regulating the reprogramming of the metabolic pathways in cancer cells. LncRNAs could regulate various metabolic enzymes that integrate cell malignant transformation and metabolic reprogramming. In addition to the known functions of lncRNAs in regulating glycolysis and glucose homeostasis, recent studies also implicate lncRNAs in amino acid and lipid metabolism. These observations reveal the high complexity of the malignant metabolism. Elucidating the metabolic-related functions of lncRNAs will provide a better understanding of the regulatory mechanisms of metabolism and thus may provide insights for the clinical development of cancer diagnostics, prognostics and therapeutics.

Long noncoding RNA SNHG12 facilitates the tumorigenesis of glioma through miR-101-3p/FOXP1 axis

The increasing vital roles of long coding RNA (lncRNAs) in the glioma tumorigenesis have renewedly and roundly recognized. Nevertheless, the in-depth that lncRNAs modulate the gliomagenesis is still elusive. In this research, we focus on the functional study of lncRNA SNHG12 in the glioma pathogenesis. SNHG12 expression was enhanced and high-expressed in the glioma clinical tissue samples and cell lines, especially in the advanced clinical grade. In functional study, knockdown of SNHG12 impaired the proliferation, induced the apoptosis in vitro and, meanwhile, inhibited the tumor growth in vivo. In mechanistic study, it was found that SNHG12 harbored the complementary binding sites with miR-101-3p at 3'-UTR, acting as a miRNA 'sponge'. Furthermore, miR-101-3p also targeted the 3'-UTR of FOXP1 mRNA. The three elements construct the SNHG12/miR-101-3p/FOXP1 axis. Overall, we confirmed a functional regulatory pathway that SNHG12 and miR-101-3p regulated the expression of FOXP1 in glioma cells, forming the SNHG12/miR-101-3p/FOXP1 pathway. This finding might act as a valuable target for glioma.

LncRNA SNHG20 knockdown suppresses the osteosarcoma tumorigenesis through the mitochondrial apoptosis pathway by miR-139/RUNX2 axis

Increasing evidence has indicated the important roles of long noncoding RNAs (lncRNAs) in human osteosarcoma tumorigenesis. In present study, we aim to investigate the roles of lncRNA SNHG20 (small nucleolar RNA host gene 20) in osteosarcoma tumorigenesis and explore the in-depth molecular mechanism. Results showed that lncRNA SNHG20 expression was up-regulated in osteosarcoma samples and its high-expression indicated the poor prognosis. Loss-of-functional experiments indicated that SNHG20 knockdown inhibited the proliferation, invasion and induced the apoptosis of osteosarcoma cells in vitro. Specifically, SNHG20 knockdown up-regulated the expression levels of caspase-9, caspase-3 and Bax, indicating that SNHG20 knockdown accelerated the apoptosis of osteosarcoma cells via mitochondrial apoptosis pathway. Bioinformatics analysis revealed that miR-139 both targeted with the 3'-UTR of runt-related transcription factor 2 (RUNX2) and SNHG20, which was verified by luciferase reporter assay and RNA immunoprecipitation (RIP). In conclusion, our data reveals that lncRNA SNHG20/miR-139/RUNX2 axis modulates the osteosarcoma tumorigenesis and apoptosis via mitochondrial apoptosis pathway, providing a novel insight for the pathophysiological process.